Light controlled musical instrument



July 15 192 M, s. DUGOUT LIGHT CONTROLLED MUSICAL INSTRUMENT 2 SETS-SHEET 1 Filed Aug. 10., 1949 Inventor:

IL BCEL STANISLAS DUCOUTL Juiy 15, 1952 M. s. DUCOUT 2,603,118

LIGHT CONTROLLED MUSICAL INSTRUMENT Filed Au 10, 1949 2 SHEETS-SHEET 2 'Inventor:

LIARCEL STANISLAS DUCOUT e Attorney Patented July 15, 1952 LIGHT CONTROLLED MUSICAL INSTRUMENT Marcel Stanislas Ducout, Paris, France Application August 10, 1949, Serial No. 109,433

In France September 21, 1948 13 Claims. 1 It is one of the objects of this invention to provide a musical instrument particularly for sound reproduction controlled at a distance by the movement of one or more dancers.

' Ordinary musical instruments of the string or piano type require physical contact with the instrument, either through the hand of the musician or through an implement held by the musician. The instrument is actuated only when the hand engages the string or the piano directly or indirectly. The movements of the hand of the pianist, while passing from one key to another, are without influence on the sounds emitted.

On the other hand, in musical instruments of the radiophonic type, it is known to produce sounds without physical contact between the performers hand and the sound producing parts. In this case, however, the performer must be very close to the apparatus (not more than several inches away), and in order simultaneously to modify two characteristics of sound, for example pitch and intensity, these radiophonic instruments, require, in principle, the intervention of two movable parts, i. e. the two hands of the performer. In addition, these instruments are not in commercial use, because they produce a progressive variation in sound pitch and thus include notes which are musically false. It is very diflicult to avoid these false notes as a function of the position of the hand of the performer in'space. It is still more difficult to attain the necessary precision in combination with dance movements.

The apparatus according to the invention has been conceived to permit the modification of two sound characteristics, pitch and intensity, for example, in a non-physical fashion, 1. e. without contact with the sound apparatus and as a function of displacement in two different directions of the same movable member, for example, the hand of a performer carrying a signal light.

The sound modifications thus obtained occur inra continuous fashion as a result of the dis! placement or the signal light; the pitch of the sound'varies stepwise i. e. passing by quarter tones, half tones or full tones, from one correct musical note to another, while avoiding intering-from the movable-source into a narrow beam' anism provided. This may conveniently comprise a photo-electric cell and an associated loud speaker system.

In accordance with the invention means are also provided for varying the intensity of the sound producedand comprise light screening means disposed along the optical axis of the objective lens system in proximity to and of a width at least equal to the series of sound tracks on the scanning disc. The screening means provided has a substantially constant degree of opacity in the direction of a radius projectedfrom the center of said disc parallel with the screening means, and a variable degree of opacity in the transverse or tangential di rection, so that when the source of light is moved in such transverse direction the produced musical note is varied in intensity by reason of the relatively greater or lesser amount of light which is transmitted through the screen to the scanning disc.

Thus when the source of light is moved in a radial direction relative to the scanning disc, different musical notes are produced while movement in a tangential direction modifies the volume of the sound.

The sound tracks on the scanning disc being so selected as to produce predetermined different frequencies, different musical notes of correct predetermined pitch will be separately produced as the light beam passes radially from one track to another. The intensity of the sound, on. the

otherhand, will be continuous as the light beam moves in a direction of radial transference from one soundtrack to another, so long as such radial movement is not accompanied by move-. ment of the light beam in the direction tan-- gential to the sound track.

Thus. the two variables are distinct and separate from each other and may be used in sequence to eifect the widest variety of musical tones and intensities.

The light impulses passing through any convergent lens system and the second objective lens system, to effect a still further modification of the harmonic content of the sound.

The drawings annexed hereto represent in a schematical fashion and in the form of: examples only, several embodiments of the invention.

Fig. 1 shows in perspective the arrangement of the various elements constituting an apparatus according to the invention.

Fig; 2 is a schematic drawing showing theposition ofthe apparatus in relation to a performer.

Fig. 3 is a diagram showing the functional principle of the apparatus.

Fig. 4 is a partial view similar to that of Fig. 1 showing the arrangement of several accessory parts of the apparatus.

Fig. 5 represents a schematic plan view. showing disposition of the principal parts of the apparatus shown assembled in Fig. 4.

Figs. 6 and 7 show two accessory devices permitting the performer to control his'movements with respect to the sound'producer.

Figs. 8, 9 and 10 show in perspective three particular devices for the production of light signals.

The apparatus represented schematically in Fig. l is actuated by one or more signal lamps 1 adapted to be carried by hand by one or more performers, for example by dancers. These lamps may be provided with a reflector 2 or the like.

-The apparatus itself comprises an objective lens or system of lenses 3 for receiving the light from source I, the objective lens or system of lenses 3 concentrating the light into a narrow beam. When therefore the light source I is carried (Fig. 2) in the handof a performer, moving in horizontal direction OX and in vertical direction OY, the image of the light source produced by the objective lens will describe a curve in a plane perpendicular to the optical axis of the objective lens. This curve such as curve C' (Fig. 3) is inverted by the objective lens with respect to the curve described by the light source and each point of the curve corresponds to a predetermined sound pitch and'a predetermined sound intensity, as will be described more fully below.

To the. rear ofobjective lens 3, there are disposed a screen 4 and rotary disc 5 in closeproximity to each other, said membersbeing adapted to. musically interpret the. above mentioned two displacements of the light source. V I

Member '4 is a screen having a varied light transmitting power andit. extends over the entire fieldto'be scannedby the light beam from source I. As shown in Fig. 1 the opacity of screen 4' 1. e. parallel to a radiusof the discs and varied in a vertical direction i. e. tagential to 'saidr'adii,

for. example, increasing from the bottom to thetcp. It 'will be appreciated that in differentdis-I positions of the screen 4 relative to the sound tracks Tofthe disc 5 the directions in which the screen has constant and variable opacitles will change. As shown in the drawings screen 4 is in the form of a prism.

Member 5 is a disc rotated at constant speed by an electrical motor 6, for example. On the periphery of disc 5, there are disposed several circular tracks over a width substantially equal to that of screen 4. These tracks. are. formed of perforations or slits l. The number of slits varies from one track to another. In each row or track the slits are equidistant from each other; three rows only are shown in Fig. l and six rows in Fig. l. The slits in different rows pass a given point at different frequencies and therefore excite notes of different pitch.

Behind the disc. 5, there may be arranged a light condenser 8 in the form of a lens or system of lenses which serves to concentrate the light rays passing members ti and 5, upon a photoelectric cell 9. Cell 9 is disposed substantially in focus of condenser 8.

The light variations received by cell 9 are transformed into sound waves by a radio-electric amplifier [0 of well known construction, com-' bined with a loud speaker I I. It is apparent'that as a result of the disposition just described, thedisplacements of light source I in direction; QY: in the arrangement as shown in Fig. 1,, will be; translated into variations of intensityof the'light beam passing screen 4' and disc 5, and cons??- quently into variations of intensity of soundpro duced by photoelectric cell 9 and apparatus l0 and H. The displacements in direction OXQinthe arrangement shown in Fig. 1, will producea.

the variation in intensity will be regularly;- pro gressive as a function of the opacity of screen-4 while the variations in modulation Will-be dis continuous, because each of the sound tracks; 1 comprises a number of slit determined'asafun c. tion of the rotational speed of thedisc. In thisway, sounds are produced varying from one-track; to another by a half tone" or a quarter tone, foe; example, i. e. by notes which are musicallypor rect.

Fig. 2 shows the manner in which the-optical axisv Z-Z of objective lens or lens system 3- is.

preferably disposed, and along which members-- 4, '5, 8 and 9 are aligned.

This axis ZZ is preferably slightly; inclined; above a horizontal plane in such a mannerthat;

the. most frequent position of the 'handscarryar ing the signal lights, i. 'e: the position atjthe: height of the breast, is approximately-mthe transversal optical symmetry planeofithez obj 60. tive.

It will. be noted from Fig. 2 that the sameappm ratus. such as described maybe: utilized toreceive simultaneously several movable. signals: or light: beams emitted by light sources carried by sneer more dancers each causing a corresponding sound emission, with all these emissions beingmixed in the radioelectric apparatus Ill- I.

If it is desired to modify the'harmonie 'contentiof sound emitted by the apparatusame select arbitrarily a particularhannciim (3"(5I iffl3tZ- the apparatus may be equipped with members such as represented in Figs. 4 and 5. These members consist of convergent lenses [2 disposed between objective lens 3 and screen 4 and extending over-the entire width of the screen 4. It is possible to provide as many lenses l2 as there are perforated circular tracks I on disc 5'. Each of these lenses have a rear surface formed'in such a manner that the rays received thereon are made parallel to optical axis Z--Z.

Between disc 5 and condenser 8, there are also provided convergent lenses l3 corresponding to the number of perforated circular tracks I of disc 5. Lenses l3 redirect the luminous rays toward I condenser 8. Finally between lenses I3 and disc 5, there are disposed as many masks 14 as there are perforated circular tracks 1. Each mask [4 is divided into an opaque zone and a transparent zone as shown in Fig. 4, such division occurs along a line the contour of which modifies the harmonic content of sound in accordance with principles .well known in photographic sound recording. The masks i4 may also be of the varied opacity type.

Accordingly, the circular tracks of slits in disc 5 scan each mask Hi, the height of which equals the distance between consecutive slits in each sound track. This procedure is well known.

Rotary disc 5 is preferably made of thin material which is relatively flexible so that during rotation the screen is maintained by the centrifugal force-in a plane normal to the axis of rotation.

In the same manner as a pianist, for example, must take into account his position with respect to the piano, in the present case, the performer must be able to trace with respect to the instruments, his distance and lateral position-which is the purpose of system of Fig. 6and also if necessary the position of the signals lightswhich is the purpose of system of Fig. 7.

The apparatus assembly just described, 1. e. members 3 to II and also [2, I3 and-I4, is disposed in a box IE (Fig. 6). On the front panel of box [5, there is placed the objective lens 3. Box [5 also comprises a sight member consistingfor example of a white cross it placed over that front panel. member is disposed in the form of an opaque cross ll supported on arm i8 sliding in guide 19. With this a performer is able to verify his position with respect to the apparatus when cross I! is projected or appears superimposed on white cross [6.

The adjustment of the aiming device is effected by adjusting the distance of aim member I! with respect to the position of sight member Hi. This is achieved by causing arm I8 to slide in guide I9. The aiming device may be provided with a luminous indicator such as represented in Fig. 7, and placed in the neighborhood of the apparatus. This luminous indicator is composed of several reflecting plates 20. Each plate corresponds to a musical note, i. e. to one of the perforated circular tracks I of disc 5, and is arranged with respect to the vertical plane passing through optical axis ZZ of the musical instrument at such angle that each plate reflects a lurninous ray at the performers eyes (represented as seen from above upon the drawing), i. e. appears luminous only if signal lamp I (Fig. 1) is in a position where its image as formed by objective 3, is projected upon the perforated circular track 1 corresponding to that particular plate.

It will be noted that the only connectionexisting between one of these plates 20 and one of the In front of cross it, an aim perforated circular tracks 1 of the rotary disc g is the following:

As soon as light source I (Fig. 1) occupies a certain position in space, objective 3 produces an image thereof upon one of the perforated circular tracks I. At the same time, the corresponding plate 20 (Fig. 7) reflects the rays of light source 1 into the eyes of the observer.

Fig. 8 shows a suitable form for a signal lamp. Lamp I has a filament which is as close to being a point source of light as possible, and is mounted with its reflector 2 in a blackened box 2| provided with a window 22. Window 22 is formed of glass which, if desired, may have a graded transparency, to vary the intensity of the beam of lamp l and thus the intensity of sound reproduced as a function of the angular orrotated orientation of the box 2| with respect to the plane ZZ, that is, dependent upon the portion of the glass window 22 through which the light rays reaching the objective lens 3 have passed.

The particular signal lamp of Fig. 8 can be used in a musical play to effect a soft commencement of a note. It does not serve however, the same purpose as the variation of intensity of sound in accordance with the position of the lamp in space.

Box 2| is provided with a ring 23, preferably elastic, for fitting over the finger of the performer.

Lamp I may be supplied by electric cable 24 connected either to a fixed outlet or to a battery carried by the performer.

Fig. 9 shows an arrangement in which lamps I carried by the performer are supplied with energizing electric current from a radioelectric transmitter 25 the radiation from which is directed into the working plane of the performer and which is received by aerial 26 carried by the performer and connected to signal lamps I to excite.

them.

As shown in Fig. 10, signal lamp I may be replaced by a reflector of a standard type 27, to

reflect the light of a fixed light source 28 to the.

able light projector, means for modulating thelight from said projector and means for transforming said modulated light into musical sound waves, said. modulating means comprising an ob jective lens system for receiving and concentrating the light rays into a small beam having a direction which varies in accordance with the movement of the light projector, a rotatable disc mounted on an axis substantially parallel to the optical axis of said objective lens system, said disc having a'series of circular bands of perforations of differing predetermined frequencies therein and positioned to move said perforations across the optical axis of said objective lens system in such a manner that when said light pro--' jector is moved in a direction which is parallel. to a radial direction on said disc said beam passesfrom one circular band of perforations to another to change the pitch of the musical tone produced, and light screening means mounted near to said.

disc and across the optical axis of said objective,-

said screening means having a substantially constant degree of opacity in said radial direction: and a varied'degree of opacity in a transverse direction substantially at right angles to said radial direction, whereby on movement of the lightpro-.

jector in said transverse direction the intensity of the musical tone produced is varied.

2. Apparatus according to claim l which includes an aiming device for a manipulator of said movable light source comprising a sight member disposed approximately perpendicularly to the optical axis of. said apparatus and an adjustable aim member disposed. in front of said sight member.

3. In 'alight-responsive musical sound produc-. ing. system in which the selection of at least one.

oi-a series of musical notes is effected by projecting alight beam across the path of a selected track in a. series of tracks of. perforations provided in. a moving surface, said perforations in each track having a predetermined uni-form spaced relationship, to cause light impulses to be.

transmitted through a given point on said moving surface at a given frequency, the spacing be-.

tween the perforations being different for each track in accordance with the speed of movement of: each track across the path of the beam to produce correctly pitched musical: tones in said sound producing system; the improvement which comprises light screening means disposed in front ofsaid tracks and having a constant light transmitting power in. the direction of movement of the light beam from one track to another and a variedlight transmitting power in a direction transverse to said: first mentioned direction, whereby on. movement of said beam along said transverse direction variations in said intensity. are produced.

4. In. a light-responsive musical sound producing system including a. movable source of light, optical light-receiving means in the path of light from said source, an amplifying system, a photoelectric cell and a. scanning disc having a series of. circularly disposed radially spaced tracks of perforations for transmitting light impulses from said light-receiving means at selected frequencies to, said. cell; the improvement consisting of sound-intensity varying means comprising screeningmeans. formed of a light-transmitting medium disposed in the path of the light from said source to said disc, said medium having a substantially constant light-transmitting power in the radial direction of movement of said light from one track to another and having a Varied light-transmitting power in a direction tangential to said first mentioned direction, whereby on movement of. said light along said tangential direction variationsin sound intensity are produced.

5; In a. light-responsive musical sound producing system as set forth in claim 3 and further including at least one movable light source for projecting the light beam and an objective lens system positioned between the light source and the moving surface for receiving light rays from the source and for concentrating such rays into a relatively thin beam having a direction which varies. according to the position of the source; the. light screening means as set forth in claim 3 in combination with a series of convergent lenses.

disposed between the objective lens system and saidscreening means equal in number to the 13% System; the combination asset forthin claim 5 and: further comprising a series of masks equal in number to the number of tracks of perforations. anddisposed across the. paths ofthe light rays and in alignment with the respective tracks.

eachmask being of varied opacity.

7. In a light-responsive musicalsound produc-;.

ing system; the combination as set. forth lnclaim. 5 further comprising a series of masks squat-in number to the number of perforations; each mask having a relatively opaque zone and a relatively transparentzonedivided on a line. for modifying the harmonic content of the sound to a .prede-;. termined degree, saidmasks beingdisposedacrossi the path of the light rays with each maskain, alignment with its respective: track ofxperfottae.

tions I 8-. In a.light-responsive musicalsound produce. mg. system; sound intensity varying means-asset:

forth in claim 4- in combination with aiming.

means for a manipulator of the movable light: source, saidaiming means comprising a sight.

member disposed substantially perpendicularly to the optical axis of the light-receiving.,means,.

and an adjustable target member disposedin front of said sight member.

9. In a light-responsive musical sound producing system; the combinationas set forthin claim- 7 further comprising a series of reflecting-plates of a numberequalto the number of track's on-said moving. surface, said: reflecting plates being dis:

posed'with respect to a manipulator of said mow.

able light source to reflect light rays'back to said manipulator in consonance with thebeami'n'g.ctv

the raysfor transmission through. any selected.

one of the tracks of perforations.

10. Ina light-responsive musical sound pro-.-- ducing system; light screening means according to claim 3; in combination with a screen having,

1; wherein said: light projector includes a fixed;

light source and a movable reflector for receiving light from said source and reflecting said light to said objective lens: system.

13; Apparatus. for the light controlled produc-.;

tion of musical sound waves as set forth in claim 1 wherein said light projector. includes a radioelectric'wave transmitter, a portable antenna-'dise. posed in the field of said transmitter, and: an.

electric lamp operatively connectedto' said an.-: tenna to lac-energized in response: to the trans mitted radio-electric wave.

MARCEL STANISLASDUCOUI};

REFERENCES CITED The following references are of record in the file of this patent:-

UNIIED STATES PATENTS Number Name Date 1,948,996 Toulon Feb.- 27, 1934, 1,986,547 Winch dan, 1,1935- FOREIGN PATENTS Number Country Date, 

